1. Field of the Invention
The present invention relates to a method and apparatus for transmitting and receiving UpLink (UL) data in a mobile communication system. More particularly, the present invention relates to a method and apparatus for transmitting and receiving UL data using multiple carriers in a mobile communication system.
2. Description of the Related Art
Mobile communication systems have been developed to provide communications, with the user mobility secured. Due to the rapid development of mobile communications technology, these mobile communication systems can now provide not only voice communication services but also high-speed data communication services.
Recently, standardization for a Long Term Evolution (LTE) system, one of the next-generation mobile communication systems, is underway in the 3rd Generation Partnership Project (3GPP). The LTE system is technology for realizing high-speed packet-based communications having a transfer rate of up to 100 Mbps, which is higher than the currently available data rate, and its standardization is almost complete. In line with the completion of the LTE standardization, an LTE-Advanced (LTE-A) system is now under discussion, which improves a transfer rate by combining the LTE communication system with several new technologies. The term ‘LTE system’ as used herein may be construed to include the legacy LTE system and the LTE-A system.
One of the newly introduced technologies is Carrier Aggregation (CA). CA is technology in which a User Equipment (UE) transmits and receives data using multiple carriers. The UE transmits and receives data through specific cells (generally, cells belonging to the same evolved Node B (eNB)) of aggregated carriers, and this is equivalent to transmitting and receiving data through a plurality of cells by a UE.
In the mobile communication system of the related art, in single-carrier UL transmission, a UE calculates required transmission (Tx) power taking into account the amount of scheduled resources, a coding rate, a channel status, etc. and determines the final UL Tx power by limiting (or defining) the calculated required Tx power as a specific maximum Tx power.
However, a method and apparatus for determining UL Tx power in multi-carrier UL transmission by a UE in a mobile communication system has not been discussed yet. Therefore, there is a need for a method of determining UL Tx power for each carrier so that a UE may minimize interference to other frequency bands or other cells while maintaining its required Tx power if possible.